Event sourcing infrastructure implementation

Question

I implement Event Sourcing and CQRS pattern in my application. I inspired by CQRS journey where I downloaded sample code. There I found whole infrastructure for Event sourcing (CommandHandlers, EventHandlers, Events, Envelopes ... etc.), but it is quite big amount of code and I can't imagine that I need all of code for my simple Event sourcing.

Do you know some common tested library/nuget package/project containing all infrastructure for sending/registering commands, events and everything what I need in Event sourcing pattern? Or should I implement it by myself?

Answer 1

May I introduce this .NET Core 2.x based event sourcing framework: https://github.com/jacqueskang/EventSourcing/

It provides base classes for implementing events, event-sourced entities, entity repositories, and several simple event stores to persist events in text file or in database (using EF Core).

It's especially easy to be integrated in a ASP.NET Core web application, I have a pretty simple demo here.

Welcome any contribution or comments!

Answer 2

The general recommendation is to not write your own event store. Sure, you can write your own ES, but do it only for educational purposes. For production systems I would recommend you to use an existing ES. It might look like a lot of unnecessary infrastructure code at first but you will soon notice that you do need it. In its simplest form ES is not that hard but once you start dealing with concurrency, performance etc it will be more complicated.

NEventStore and Event Store are two well known event stores.

As a side note from my own experience, do not underestimate the time that you will need to invest on infrastructure code even if you use an existing ES.